Traffic signal



May 28, 1946.

TBAFFIC SIGNAL Filed dot. 1a,".1944 4 SheetsSheet 1 (inventor JZ M (lttorneg W.YJ.LEPPERT 2,401,171"

May 28, 1946. w. J. LEPPERT TRAFFIC SIGNAL Filed Oct. 1a, 1944 4 SgeetS-Sheet 2 3nventor WQTQ attorneg utmmmh nr ww w. J. LEPPERT May 28, 194

TRAFFIC SIGNAL 4 Sheets-Sheet 3 Filed 001;. -18, 1944 May 28, 1946.

w, J. LEPPERT 2,401,171 v TRAFFIC SIGNAL Filed Oct. 18, 1944 4 Sheets-Sheet 4 Snnentor Patented May 28, 1946 PATENT OFFICE TRAFFIC SIGNAL William J. Leppert, New Orleans, La.

Application October 18, 1944, Serial No. 559,221

8 Claims.

The present invention relates to improvements in traflic signals.

The present invention deals with the problem of correcting provable flaws in existing methods of devising and constructing the standard street signals used throughout the country and abroad for controlling motor vehicle traflic and adequately advising pedestrians at controlled street intersections.

The several varieties of signal devices used for this purpose on the streets are open to numerous criticisms. They are, without exception, overly heavy; they are extremely fragile; they are made, in many instances of material fashioned as castings of low grade; they involve necessity of high skill for installing and servicing; they are costly beyond need and they involve the use of fragile light bulbs to a number far in excess of actual scientific requirements. This latter fundamental fault stems from a misconception of the fundamental principle of a traffic signal device.

Manufacturers of street signal trafllc devices were led into error by wrongfully believing that the light emitted by the signaling device should be projected in a conelike shape after the manner found in lanterns, flashlights, or automobile headlights. In each of these devices one finds that the source of light throws its beams upon one or more parabolic reflectors which cast these beams upon colored lenses in their path. These lenses multiply the intensity of light and, because of the reflector behind the bulb, these rays are thrown out exactly as is done with the headlights on automobiles.

Because these street signal traffic lights must show illumination in as many as four opposed directions, it naturally follows that such street signals must be equipped with four parabolic reflectors, one behind each of the needed bulbs.

That this concept is wrong has been amply proven by laboratory and street tests. All that the oncoming motorist or pedestrian requires is that, within at least 300 of approach, he can be given a vivid and unfailing warning that he is approaching a street intersection under legal control and that he must govern himself accordingly.

Reflectors of the type generally used are made of glass or brass and must be silvered like a mirror or plated with silver or chromium. These materials are costly. Because the average, street signal light is composed of three sections-a red, an amber and a green-the common street signal light has twelve op nings, three on each of its four sides. This involves the use of twelve reflectors and twelve light bulbs and multiplies unnecessarily the use of highly expensive electric wiring. It also involves the unnecessarily high cost of unneeded bulbs, their servicing and the element of burnout costs.

These signal lights also present other features open to honest criticism. In order to achieve results aimed at by the use of reflectors, the bulb is screwed horizontally into. the center of the reflector. The reflector itself is held in position against the interior side of the casing by a hinged spider which is secured by a complicated spring. The circumferential edge of the reflector is aflixed 'to the interior wall of the casing with a gasket intended to form a hermetical sealing. The bulb itself, extending vertically from its central base, protrudesthrough the wall of the casing and clears the outer surface of the casing. On the outer face of the casing is attached the door which holds the lens.

This lens is also hermetically sealedby a gasket and the entire door is swung on hinges and rigidly locked. Viewed horizontally this combination of spider plus reflector plus bulb plus lens and plus door represents a spheroid space within which the light bulb, when activated by current,

burns and creates intense heat. This unnecessary ovenlike chamber shortens thelife of the gaskets, attacks the rubberoid coating over the wiring and greatly shortens the life of the fllament within the bulb. These faults result in wholly unnecessary charges and repeated servicing and replacement.

Other objections to the generally accepted street traflic signal are:

(a) The sealing of the heated air within the spheroid creates sootlike deposit upon the circumference of the reflector and the lens;

(b) This deposit shrinks the circular reflection of light and impedes a clear understanding by pedestrian and motorist;

(c) The horizontal placement of the bulb causes the incandescent grid part of thefilament to be placed so close to the concavity of the outer .lens that thereis created a so called phantom light. This phantom. light is confusing to pedestrian and motorist at all times, but

is especially confusing whenever the rays of the ascending or descending sun strike upon them.

The present invention aims to correct the faults in the interest of protecting lives of motorists and pedestrians and in presenting to municipalities perfected street traific signals at an installation and servicing cost less than they the invention will be more fully described hereinafter, and will be more particularly pointed out in the claims appended hereto. In the drawings, wherein like symbols refer to like or corresponding parts throughout the sev eral views, 1

Figure l is a front elevational view of an ini proved traffic signal constructed in accordance with the present invention, and with partsbrpken awayand parts shown in section. Q

. Figure 2 .is a horizontal section taken on the line'2l2 of Figure 1.

Figure 3 is also a horizontal the line 3-3 of Figure 1.

Figured is likewise a horizontal sectiontaken on the line l4 of Figure .1 with the hoods shown in plan.

Figure 5 is a perspectiveview of the lamp base adjustable holder. 7

Figure 6 is avrtical section taken on an enlarged scale onthe line 66 in Figure .8 and showingthe improved channeling unit .as mounted in the .wall. of the casement which is. shown in fragmentary section. s V Figure. .7 is a similar view with the-channeling unit 'shown as detached from the easement wall.

Figure 8 is a front elevational view of-the desection taken. on

vice shown in Figure. 6 taken fromthe left hand F side of Figure fi-andwith parts broken away. and

parts shown .in section,.and.

Figure!) is a front elevation of a fragment of a wall of the casement with the channeling unit detached and removed.

7 Referring more particularly to thedrawings, I and for the present to Figuresel to 4'inclusive,

I0 designates generally a casement which may be mounted upon an appropriate base l I carried the sheet are brought together and welded, as indicated at l5 in Figure 3, or otherwise secured together. The casement It] thus has four sides, presenting a side wall to each direction of a street intersection; and the casement Ill is sufficiently high to yield three separate light compartments.

At the upper end the casement I0 is closed by a removable cover I6. Such cover l6 may be carried upon the casement and fastened thereto in any" appropriate manner. In one form of the invention as shown in Figures 1 and 3, lower opposite side edges of the cover it are formed in the inturned flanges I! adapted to slide upon the outwardly projecting edges I8 of a top plate 19 secured to the casement. Vhen the cover It is slid into'place a bolt or other fastening 20 (Figure 3) may be passed through the flange l1 and the outwardly projecting edge 8 to hold the parts in assembled relation.

The top plate l9 has an opening 2! througl'i which heat generated in the easement lii'by the lamps may ascend into the cover it and be met by' a distributing plate 22 (Figures 1 and 2). A shown in Figure 2 such distributing plate may be square or rectangular in plan and rotated angularly with respect to the corner portions of the cover it which is pyramidal in shape whereby the corners of the distributing or baffle plate 22 upon a hollow or other standard l2;for the case ment may. be suspended after any acceptable manner from an arm extending horizontally from a structureor a post orstandard.

A cable !3 let in through the hollow. standard 52 carriesthenecessary bundles'of electric wires which convey current from an external source .to

is-originally in. a flat sheet at which time twelve holes may be piercedthrough the sheet metal having a preferable diameter of. 8% inches. These holes I 4 are shown more particularly in Figures '7 and '9 and they receive therethrough the various channeling unitsashereinafter described. 1

After the holes M have been. punched in the metal the entire sheet will be placed in a break which will bend it into the form of abox or into rectangular form, as shown in Figures 3 and 4. Such box or casement will probably beapproximately thirty-six inches high. The free ends of It and the fiat sides of the plate 2?, are presented to these corner portions 23. The corners of the plate 22 may be held by'appropriate clips or fastenings 24 to the Walls of the cover i6 between the corner portion 23. Thus theascending heat directed by the central opening 2! in the top casement plate I9 is directed against the blank wall of the baffle plate 22' and caused to {move out horizontally therefrom toward and against the upwardly convergent walls of the cover l6 by which such horiznntally diverted heated air ascends along such convergent walls around the edges of the baffle plate 22"and into and through a perforation 25in the'top of the cover l5. Surrounding the perforation 25. is a ventilator having a closed top 26which overhangs the vertical tubular wall 21. In the wall 2'! are apertures 28 in the same horizontal plane with the dependent flange 23 of the closed top 2% it being understood that theflange is spaced outwardly from the perforatedwall 22 whereby to deflect the heated air issuing from the apertures 28 downwardly and outwardlybenea h the flange 29.

The top plate it may be rigidly fastened to the casement It to impart rigidity to the upper end of the casement it]. As the plate Il -projects on all four sides of the casement ll these projections form a shelf for deflecting rain.

At the bottom of the casement i0 is av bottom plate 38 which may be welded or otherwise affixed to the lower edge of the easement sheet and tends to impart rigidity thereto.- This bottom plate has one Or more slots 3| therethrough for accommodating the several sets of wires 32; 33 and M which branch from the cable l3 and are led to serve various compartments of the casement H3. The lowermost compartment" 35 is comprised between the bottcmwall 38 and a horizontal partition 38 which extends across between the four walls of the casement and is supported by angle irons or may be welded in the casement orotherwise secured in place. A secondsimilar partition 31 is mounted in the casement in spaced relation above the partition 36 so as to comprise between the partitions 36 and 31 the intermediate or middle compartment 38.

The top compartment 39 i comprised between the upper partition 31 and the top plate It. If desired a separate floor plate or partition Ml may be mounted in the casement in spaced relation above the bottom plate 39 to form the bottom or floor of the lowermost compartment 35. The partition 35 forms the roof of this lowermost compartment and the floor of the intermediate compartment 38; and in like manner the partition (serves both as the roof of the intermediate compartment 38 and the floor of the uppermost compartment 39. .Thus three vertically super imposed compartments 35, 38 and 39 are provided in the easement H1 and supported upon the base I2 which base may be ornamental if desired.

In each compartment there is but a single electric light bulb or lamp. These lamps are desig: nated at 4|, a2 and 43. From Figures 1 and 4; it will be seen that the lamps are supported with their socket axes vertically. Each lamp is mounted upon an adjustable holder, one form of which is illustrated in Figure 5. One such holder is mounted upon the fiOOr of each compartment.

Referring more particularly to Figure 5 a lamp socket 44 i shown as disposed with its axis vertically and with its base resting upon and affixed to a cradle plate 45 having upstanding slotted side Walls 46, the slots of which are indicated at 41. The side walls 36 slide up and down with the cradle plate 45 between vertical carrier plates or walls 48 Which are suitably erected and aiiixed upon the fioors of the compartments. The flanges or feet 49 may be suitable for this purpose and to provide ample surfaces for welding, brazing or otherwise afiixing the carrier plates to the compartment bottoms, both of which members may be advantageously of metal. Bolts 59 pass horizontally through the carrier plates 48 and through the slots Bl of the side walls 45. The head 5! of the bolts and the winged or other nuts 52 may be wider than the widths of the slots 4?. By loosening the nuts 52 the cradle plate 35 carrying the lamp socket id and the lamp therein may be moved up or down; and after adjustment the nuts 52 may be retightened to preserve that adjustment.

It is important to observe that in accordance with this construction the light bulbs are screwed vertically (and not horizontally) intothe adiustable sockets M, the height of which may be manually adjusted. Thus the illuminated grid section or filament in the bulb can be exactly leveled with the center of each of the four lenses of the channeling units as hereinafter described and as shown by the circled background in Figure 1.

Thetwin wires 33 from the cable It lead-upwardly through the slot 3! of the bottom plate 30 and a central opening of the bottom partition 40 and are connected with the socket M in the lowermost compartment 35.

The twin wires 34 are directed to the left and pass upwardly through corner portions of the partitions 40 and 35 asshown in Figures 1 and 4 and emerge in the central compartment 53 where they are connected to the socket in that compartment. While the wires 34 pass through vertically aligned openings in the partitions 40 and 35, such wires are led through elbow 53 and 56 to avoid the light from one compartment spreading to another compartment.

The twinwires 32 branch to the right in Figure 1 and ascend through elbows 55 arranged at the opposite corner portions of the partitions 49, 36 and 31 to bring the wires or leads 32 into the uppermost compartment 39 where the same are connected with the light bulb socket in that compartment. i

The partitions 40, 36 and 31 may be square pieces of metal rigidly aflixed to each of the four sides of the casement box and are preferably solid except where pierced for wiring and ventilation purposes.

Each compartment has a single lamp but four light channeling units as shown in Figure 4.

With three compartments there are twelve such channeling units in all.

One such channeling unit and its method of mounting are shown in Figures 6 to 9 inclusive. In Figure 9 a fragmentary portion of the casement is shown in which one hole or opening l4 appears. About this opening I4 is a ring 55 which is spaced radially outwardly of the opening I4 and which outstands from the outer face oi the casement wall 10 as more clearly appears in Figure '7. This ring may be of metal, welded or otherwise secured to the casement wall It). Also carried by the casement wall at the top of the ring 56 is a lug 51.. Also carried by the easement are detents or finger latches 58 pivoted upon the pivots 59 and having the offset free ends Ell. 'As shown in Figures 8 and 9 these finger latches or pivot detents 58 are three in number with one at the bottom of the circle of the ring 56 and two at the upper side portions of said ring.

Referring more particularly to Figures 6 and 7, the light channeling unit comprises a frustoconical casing 6| to the smaller end of which is attached a tubular lens holder 62 having a diagonal flange 63 which externally laps the smaller end of the casing 6i andmay be welded or otherwise afiixed thereto. A vertical inturned flange 64 on the small end of the cone casing 61 constitutes an abutment for the edge of a small convex colored lens 65. The rim of this lens 65 slides freely in the tubular lens holder 63. A disc diffusion lens 66, preferably of white flash glass, is also slidably mounted in the tubular lens holder 62 and moved up against the circular rim of the small convex colored lens 65. A retainer ring c1 of spring wire serves to retain the diffusion lens 66 in place and incidentally to also hold in place the small convex colored lens 65. The retainer ring 61 is mounted in a swivel keeper 58 carried within the tubular lens holder 62 to enable the retainer ring 61 to be swung out to the position indicated in Figure 6 to admit the lenses and to permit of the removal of the same. The lower spaced ends 69 of the split retainer I ring El are outturned downwardly into parallelis'm and are in juxtaposition, as indicated in Figure 8, for convenience in being simultaneously grasped by the hand of the operator and squeezed together whereby to free such ends 69 from undercut notches II in the lower part of the tubular lens holder 62 into which such outturned ends $9 are automatically moved by the inherent resiliency of the spring retainer ring 6'! in attempting to expand radially outward. A slot l9 communie cates with the undercut notches H and opens through the inner edge of the tubular lens holder 52 to permit such outturned ends 69 "when squeezed together to swing on the swivel keeper to out of the slot 10 and to the position indicated in Figure 6. l

A hood 12 of a conventional form is carried at the larger endof the cone casing 6|. The need T2 is carried by a ring 19 which may be integral with the metal stock of the hood. This ring 79 has an outturned flange 13 which abuts against an outturned flange M of the large end of the frusto-conical casing til. It will'be noted from Figures 6 and 7 that the flange M is deeper in a'radial sense as compared with the flange 13 which produces a shoulder or abutment against which the ring edge of the large convex colored lens engages, such lens being slidable from the outer side into the hood ring 19 in which it is retained at the outer side by a retainer ring E6 of spring wire carried by a swivel keeper i! .mounted at the upper portion of the hood ring F9. The outturned free spaced ends l8 of the retainer ring Ki cooperate with a slot 8!] and undercut notches 8| i the hood ring 19 similar to the parts 1!! and H previously described. The swing out position of the spring retaining ring is shown in Figure 6.

An attaching ring 82 is affixed externally to the hood ring 79 and preferably to the flange 13 thereof. The flanges 13 and I l and the attaching ring 82 may all be of metal and welded together or afiixed in any other'suitable manner. l h'e attaching ring outstands beyond the outer edges of the flanges l3 and i4 and carries a right angularly turned flange 83 substantially concentric with and spaced radially outwardly from the flanges 73, M. The attaching ring 82, its flange 83 and the combined flanges I3, 14 constitutes an annular groove for rather snugly receiving'the casement ring 55; or more properly speaking for fitting upon three sides of the ring 55, the inner side of the ring being against the casement Wall.

As shown in Figure '6, the flange 83 lies outwardly of the ring 55 with the flanges 13, M lying radially inward of the same and with the inner flange M lying against that area'of the casement wall that is included Within the ring 55. The attaching ring 32 lies against the outer face of the ring 56. Thus the casement ring 56 and the attaching ring 82 and its associated parts including the flange 83, i3 and "M form a mechanical couple for interfltting to center and orient the channelin unit upon the casement in correct positional relationship to the casement opening or hole I4; The flange 83"is made at its top portion with a notch 84 constructed to rather snugly fit about the casement lug 51. This is for the purpose of rotationally or angularly orienting the channeling unit with reference to the casement opening and with respect to the vertical and to the horizontal'in order that the hood 12 and the cross ribs of the lenses 65 and 15 may vandalism, of the conventional outer lens found in the usual type traflic signal light. When this outer lens is broken in those lights, the bulb, unless it too is broken, sh'ows merely as a white light. It .is obvious that the motorist or pedestrian is without a warning advice to govern him-'- self. In the improved channeling unit, even though an outer red or green or amber lens is broken, an inner lens of the same color would remain unbroken. In other words the people governed by the light are doubly protected by the channeling unit than under the conventional type of traffic light now in use.

In the intermediate compartment 38 of the casing all four of the light channeling units will have amber colored lenses. In other words both inner and outer convex lenses 65 and, 15 of the four units will all be of amber colored glass.

In the top and bottom compartments of the casing both lenses of each channeling unit will be red or green, it being understood that two diametrically opposite channeling units in each compartment will have green colored small and large. convex lenses and the other two diametrically opposite units will have both convex lenses red in color; with the red lenses alternating with the green in said top and bottom compartments so that when the lamp 53 in the top compartment is illuminated and both other lamps GI and 42 dark, green lights will be seen at opposite sides of the signal in one direction and red lights at opposite sides of the casement in an intersecting direction. When the lamp t! is illuminated, and the other two lamps 42 and 43 dark, the lower compartment will show two green lights in the directions in which the red lights of the top compartment appeared and two red lights in the directions in which the green of top compartment appeared. The timing device in accordance with conventional practice will energize the lamp 42 of the intermediate compartment 38 between each change of signals and when such lamp 42 is energized it will show an amber color in all directions.

To a marked degree the easement 10 covers the element of stability and structure. Rigidity of the entire reinforced three compartments lies in the fact that the casement is a solid piece and not composed of separable elements,

There are no doors whatever in the casement. This construction eliminates the twelve doors customarily used. The ease with which the light channeling unita complete assemblymay be removed from the face of the casement structure eliminates all need of doors, all hinges and locks.

When the single lamp is illuminated in a compartment its rays strike the disc lens 56 of white flash glass which diffuses the light to all parts of the concave side of the smaller colored lens 65. This colored lens is a spread light lens and it spreads the light rays to all parts of the interior "of the concave side of the outer convex colored lens which thus presents to the eye of the motorist at a suitable distance from the signal an area of colored light suitable for conveying the necessary warning signal.

There are no reflectors in the unit. The light, diffused by the lamps, sifts through the white flash glass 65, strikes the inner spread light lens 65, and is channelled, without reflectors, to the circular outer lens I5.

Placement of the smaller lens as is done in 'the channeling unit, coupled with the use of the The casement is a solidly builtsingle unit and not an assembly. It involves rigid construction due to its rectangular assembly and to its arrangement of partitions and to its top and base units, Moreover the easement provides ample and constant ventilation in which the air ascends through the open base l2, slot 3| and through the elbows through Which the wires pass. The heat produced by the three bulbs will create convection currents drawing cold air up through the base and requiring the egress of the warm air out of the ventilator 26 at the top which will protect the interior of the easement from the elements.

The interior wiring is so staggered at opposite corners, as to assist, instead of confusing, repair men in tracing the wiring. The vertical placement of the light sockets, as against the horizontal placement, minimizes damage from road vibration and protects both wiring and filaments.

The adjustable socket table at the bottom of each compartment permits actual, easy and quick focusing of grid regardless of size of light bulb used.

The casement may be fitted with conventional tops and bottoms. The particular construction of the casement and the particular construction of the base and the top cover are all desirable and preferable constructions but they may be varied without departing from the spirit of the invention.

The easements have no movable parts, except the finger latches 58 and the adjustable light socket bases.

The snugness of fit and means of fastening the light channeling units to the casement by the three fingers 58 eliminate the necessity for doors or hinges.

The channeling units can be slipped into position by the use of the fingers alone. They require no tools for servicing.

The main feature of the invention is the construction in a traffic signal of an arrangement of compartments that without doors, hinges, locks and gaskets and with only three light sources is upwardly. convergent walls of the cover between enabled without the use of reflector and by employment of the improved channeling unit to give dependable trafiic signal warnings at extremely low cost and at a minimum need for servicing.

It is obvious that various changes and modifications may be made in the details of construction and design of the above specifically described embodiment of this invention Without departing from the spirit thereof, such changes and modifications being restricted only by the scope of the following claims:

What is claimed is:

1. An improved traffic signal comprising hollow base, a casement supported upon said base, a plurality of horizontal partitions dividing said casement into vertically superposed light-tight compartments, lenses in said several compartments, an electric lamp in each compartment, a cable comprising a plurality of pairs of circuit wires entering through the hollow base, one pair of wires extending independently of the other wires to the lamp in the lowermost compartment, a second set of wires extending up through corner portions of the lowest and next lowest partitions and to the lamp in the second lowest compartment, a third, set of wires led independently through opposite corner portions of the lowermost and the next two higher partitions and to the lamp of the third lowest compartment, elbows in the corner portions of the partitions through which said wires are passed without permitting transfer of light from one compartment to another, said elbows being of sumcient diameter to corner'portionsof a pyramidal cover.

3. An improved trailic signal comprising a casement having a compartment therein with an opening therein, a light source in said compartment, and a channeling unit comprising a housing having lens seats therein small and large colored lenses mountedin said lens seats, and a diffusion lens mounted in said housing inwardly of the small colored lens, and means to secure said housing removably to the casement.

4. A light channeling unit for use with traflic signals comprising a frusto conical casing, a tubular lens holder carried thereb and having an abutment therein, a small colored spread light lens in said holder fitted against said abutment, a diifusion lens fitted in said holder within the first named lens, means in said holder for removably retaining both lenses in place, a hood connected to the other end of said frusto conical casing and forming a seat therewith, a large colored lens fitted against said seat, means in said hood for removably retaining said large lens in place againstsaid seat, abuttin flanges between said casing and hood, and a ring carried by said hood adjacent said abutting flanges, said ring having a flange in its outer edge concentric with said abutting flanges, said ring flange having a notch therein.

5. An improved traffic signal comprising a casement having a compartment therein, a lamp in the compartment, a lens holder in said compartment, a lens removably mounted in the holder, a resiliently expansible ring pivotally mounted in said holder for engaging said lens and having free outturned spaced ends, said holder having a slotted wall portion with uncut notches adjoining the slot, said slot positioned and arranged to permit the passage of the ends when squeezed together, said ends adapted to expand into said undercut notches when the endsare released.

6. An improved trafiic signal comprising a casement, a support for said casement, a plu- .rality of vertically spaced partitions dividing said casement into a number of vertically superposed light-tight compartments, lenses in said several compartments all communicating with the same common interior space of the compartment and facing in different directions, a single electric lamp in each compartment accessible to all the lenses of the respective compartments, electric wires brought upwardly through said casement and through said partitions to the several electric lamps, elbows in the partitions through which said wires are passed without permitting transfer of light from one compartment to another, said elbows being of sufficient diameter to accommodate said wires and to provide ventilating ducts for the passage of convection current of air upwardly through the casement as induced by the heat of the lamps, and a cover for the casement having a ventilator thereon allowing the egress of heated air from the casement.

7. An improved traffic signal comprising a case.

andradi'aliy spaced from the opening, a lug projecting off said ring, a light channeling unit adapted to be removably let in through the opening, an attaching ring on said channeling unit having a groove to encompass said casement ring on the three exposed sides thereof, said attaching ring also having a notch to receive said lug to orient the unit angulariy, and latch means on the easement adapted to engage said attaching ment having a compartment with an opening 10 ring.

therein, a lamp in said compartment, a ring afiixed to the easement outside said compartment WILLIAM J. LEPPERT. 

